Trial of 1980 murder suspect to begin this week in Skowhegan

Rita St. Peter's body was found off Campground Road in Anson. She was last seen less than a mile away -- on or near the bridge between Anson and Madison after leaving a bar in the early hours of July 5, 1980. Buy Photo

Mercier is charged with murder in connection with the death of 20-year-old Rita St. Peter, who was found dead off Campground Road in Anson on July 5, 1980.

Brenda Kielty, spokeswoman for the Maine attorney general’s office, said it’s the oldest case tried by the state since Thomas Mitchell Jr. was convicted of the 1983 stabbing death of Judith Flagg in 2009.

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Assistant Attorney General Andrew Benson will prosecute the case. Kielty said the state has 34 witnesses and expects the trial to last six to seven days.

Skowhegan attorneys John Alsop of Alsop and Mohlar and John Martin will defend Mercier as co-councils.

Because the case is 32 years old, both sides will face challenges different from those in fresher cases, said Alsop.

“There are a lot of witnesses that are no longer around, favorable and unfavorable [to us],” said Alsop. “There are sketchy memories. Those are the kinds of things one would expect.”

Snow-tire-type tire tracks were found near St. Peter’s body. An autopsy report said St. Peter was run over by a vehicle, but some of her injuries were caused by a different weapon, said Jacques in the affidavit. Sexual contact samples were taken during the autopsy.

Witnesses told police that Mercier was seen in his 1980 GMC pickup truck in the general area during the general time when St. Peter left a bar to walk or hitchhike home.

Police received written consent from Mercier to search his truck on July 6, 1980. Ink impressions were taken from the tires.

Forensic scientist Alicia Wilcox examined photos of the tire impressions taken at the crime scene and compared them to the known test impressions from Mercier’s vehicle, said Jacques in the affidavit.

In Wilcox’s report, dated March 25, 2006, she “noted that two of the partial impressions photographed at the scene had the same tread pattern as the outside portion of the rear tires said to have come from Mercier’s truck,” read the affidavit.

Jacques met with Mercier at his Anson residence on Jan. 15, 2010, to discuss the investigation. Mercier told Jacques that he knew who St. Peter was, but never met her, dated her, had her in his truck or had sex with her, according to the affidavit.

Mercier had discarded cigarettes he was smoking near the roadway. After the meeting, Jacques collected a cigarette butt and delivered it to the Maine State Police Crime Laboratory in Augusta.

Forensic DNA analyst Cathy MacMillan examined a DNA sample retrieved from St. Peter’s body and the cigarette butt obtained from Mercier, the affidavit said. She found that DNA profiles were consistent as having originated from St. Peter and Mercier.

Another DNA sample was collected from Mercier after a search warrant, Jacques said in the affidavit.

In the June 8, 2011, report, MacMillan concluded “to a reasonable degree of scientific certainty” that the sperm found on a sample taken from St. Peter’s body matched that of Mercier.

The “estimated probability of selecting an unrelated individual at random from the FBI Caucasian or the FBI African American population having a DNA profile matching Jay Mercier’s twelve locus DNA profile is less than 1 in 300 billion,” MacMillan said in the affidavit.